An audio transducer includes a cone or diaphragm that moves in response to electrical signals to produce acoustic energy (e.g., sound). Diaphragms can be made of various materials such as, for example, paper, metal, ceramics, etc. A conventional metal speaker diaphragm, for example, can be made from a sheet metal blank that is stamped into a frustum or cone shape. A center hole is punched out of the stamped cone creating an inner boundary of the cone. In many instances, however, a conventional metal cone forming process can stretch and stress metal material near the center of the cone, resulting in a cone sidewall with unsuitably large thickness variations and an increased likelihood of tearing of the inner boundary.
The drawings are for the purpose of illustrating example embodiments, but it is understood that the inventions are not limited to the arrangements and instrumentality shown in the drawings.